DERIVATIVE FINANCIAL INSTRUMENTS EFFECTS ON EARNINGS AND AOCL (Details) - USD ($) $ in Millions	3 Months Ended
Aug. 31, 2018	Aug. 31, 2017
Derivative [Line Items]
Non-operating income, net	$ 291	$ 220
Interest expense	(529)	(469)
Non-Operating Income, Net [Member]
Derivative [Line Items]
Non-operating income, net	291	220
Effects of derivative instruments designated as hedges on income [Abstract]:
Total gain (loss) on hedges recognized in income	13	107
Interest Expense [Member]
Derivative [Line Items]
Interest expense	(529)	(469)
Effects of derivative instruments designated as hedges on income [Abstract]:
Total gain (loss) on hedges recognized in income	0	0
Fair value hedges [Member] \| Non-Operating Income, Net [Member] \| Interest Rate Swaps [Member]
Effects of derivative instruments designated as hedges on income [Abstract]:
Derivative instruments	0	0
Hedged items	0	0
Fair value hedges [Member] \| Non-Operating Income, Net [Member] \| Cross-Currency Interest Rate Swap [Member]
Effects of derivative instruments designated as hedges on income [Abstract]:
Derivative instruments	(4)	0
Hedged items	5	0
Fair value hedges [Member] \| Interest Expense [Member] \| Interest Rate Swaps [Member]
Effects of derivative instruments designated as hedges on income [Abstract]:
Derivative instruments	(7)	0
Hedged items	7	0
Fair value hedges [Member] \| Interest Expense [Member] \| Cross-Currency Interest Rate Swap [Member]
Effects of derivative instruments designated as hedges on income [Abstract]:
Derivative instruments	0	0
Hedged items	0	0
Cash flow hedges [Member] \| Cross-Currency Swap [Member]
Effects of derivative and non-derivative instruments on other comprehensive income (OCI) or loss (OCL) [Abstract]
Cross-currency swap agreements designated as cash flow hedges	(14)	85
Cash flow hedges [Member] \| Non-Operating Income, Net [Member] \| Cross-Currency Swap [Member]
Effects of derivative instruments designated as hedges on income [Abstract]:
Amount reclassified from accumulated OCI or OCL	12	107
Cash flow hedges [Member] \| Interest Expense [Member] \| Cross-Currency Swap [Member]
Effects of derivative instruments designated as hedges on income [Abstract]:
Amount reclassified from accumulated OCI or OCL	0	0
Net Investment Hedge [Member] \| Foreign Currency Borrowings [Member]
Effects of derivative and non-derivative instruments on other comprehensive income (OCI) or loss (OCL) [Abstract]
Foreign currency borrowings designated as net investment hedge	$ 0	$ (64)

Nonoperating income expense including elimination of net income loss attributable to noncontrolling interests.

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Summary of derivative and non-derivative instruments impact on other comprehensive income or loss.

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Amount of the increase (decrease) in fair value of the hedged item in a fair value hedge recognized in the income statement.

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The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Total amount of gain (loss) derived from fair value hedges recognized in earnings in the period.

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Amount of the cost of borrowed funds accounted for as interest expense.

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Amount, before tax and after reclassification, of gain (loss) from derivative instrument designated and qualifying cash flow hedge included in assessment of hedge effectiveness.

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Amount before tax, after reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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